Welcome to the community @Davi_Gomes
Not completely sure, but that is likely caused by the date not being a date object. If I remember correctly you have to send a Date object instance (see example below). If that is the case there is currently no way to parse the date from the Query box.
db.mycollection.find({
"active": true,
"createdAt" : {"$gte": new Date("2021-01-12T00:00.00Z")}
})